Historical Background

G-protein-coupled receptors (GPCRs), also known as 7-transmemebrane domain receptors (7-TM receptors), have about 850 predicted members that act as cell surface messengers in response to extracellular signals, thus triggering intracellular signaling events (Kroeze et al. 2003). GPCRs are subject to activation by ligands, lights, hormones, neurotransmitters, odorants, or drug molecules, regulating various physiological functions including, but not limiting to, lipid metabolism and inflammation (Oh et al. 2010; Talukdar et al. 2011). Among these members, GPR120 was identified by searching the databases of rhodopsin-like GPCRs that belongs to the rhodopsin family of GPCRs and is conservative in human and mouse (Fredriksson et al. 2003)....